This invention relates to a fuel-injecting apparatus used with an internal combustion engine, and more particularly to a fuel-injecting apparatus which is designed to transmit the rotation speed of the shaft of an internal combustion engine to a fuel-injecting pump with the rotation angle of said shaft regulated by advancing or retarding the phase of said angle by a lubricant pressure type device for controlling the fuel-injection timing (hereinafter referred to as fuel-injection timing control device).
The fuel-injecting apparatus of an internal combustion engine is generally so designed as to cause a fuel-injecting pump to be driven by the rotation moment of the shaft of said internal combustion engine. The injection of fuel should be effected in a timing controlled by advancing or retarding the rotation angle of the shaft of the internal combustion engine in accordance with the rotation speed of said shaft. To this end, therefore, a fuel-injection timing control device is provided between the internal combustion engine and the fuel-injecting pump.
A fuel-injecting pump disclosed, for example, in the Japanese Patent Publication No. Sho 54-21,487 may be cited as a typical device, wherein the rotation of a pump shaft supplied with a drive force from the internal combustion region is converted into the reciprocating movement of a plunger by means of a cam and tappet, and the discharge and suction of fuel are effected by the reciprocating movement of the plunger.
A fuel-injection timing control device set forth in the Japanese Utility Model Disclosure No. Sho 56-99,026 (FIG. 3) may be cited as a known type. With this type of fuel-injection timing control device, the pressure of drive lubricant supplied from a lubricant pump is controlled in accordance with the operating condition of an internal combustion engine. The controlled lubricant pressure is made to act on a piston. The advance or retardation of the rotation angle phase of the internal combustion engine shaft is controlled by the movement of the piston resulting from said controlled lubricant pressure. In other words, the above-mentioned fuel-injection timing control device indicated in the Japanese Utility Model Disclosure No. Sho 56-99,026 is the type in which the fuel-injection timing is controlled by external lubricant pressure.
A lubricant pump has to be provided as a source of pressure in order to practically apply the above-mentioned fuel-injection timing control device to an internal combustion engine. In practice, a lubricant-pressurizing pump received in an internal combustion engine is applied, and lubricant is used as drive oil.
With the aforementioned fuel-injecting pump, it is necessary to lubricate that surface of the cam along which the tappet slides. When, however, a passage through which lubricant is supplied as drive oil to the fuel-injection timing control device is constructed separately from a passage through which lubricant is conducted to the lubricated section of a fuel pump, then two oil passage have to be provided, resulting in the drawbacks that an arrangement surrounding the fuel pump and fuel-injection timing control device is complicated, thereby increasing the cost of a fuel-injecting apparatus.